Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “mobility system technology”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56

Hazards Analysis and Failure Modes and Effects Criticality Analysis (FMECA) of Four Concept Vehicle Propulsion Systems

The primary objective of this research effort is to identify failure modes and hazards associated with the concept vehicles and to perform functional hazard analyses (FHA) and failure modes and effects criticality analyses (FMECA) for each. Boeing also created a Fault Tree Analysis (FTA) for each of the concept vehicles, as the FTA contains the connectivity between systems and is an accepted, top-down method to analyze the safety of an air-vehicle. Conceptual design of notional powertrain configuration for each of four (4) NASA RVLT (Revolutionary Vertical Lift Technology) Concept Vehicles were developed in as much detail as was necessary to support the reliability and safety analysis for this project. Functional block diagrams from each of the conceptual powertrain configurations were created and used to order the FHA, FMECA, and FTA. Hazards were identified and the severity of each were categorized in the FHA for use in a follow-up FMECA. The FTA took inputs from the FMECA and the functional block diagrams to develop the connectivity and develop a quantitative architecture that could be used to perform sensitivity studies, as related to vehicle safety.Guidelines for reliability targets for both the air vehicle and the operation in the UAM (Urban Air Mobility) mission are discussed. An industry literature search was performed in order to assess gaps in existing government regulations and industry specifications. The industry literature search led to air-vehicle and operational reliability discussions, as related to Distributed Electric/Hybrid-Electric Propulsion (DE/HEP) system operating in the UAM role. A discussion of results and recommendations for future work is also provided.

Hazards Analysis↗

A Life Cycle Analysis Framework for Point Source Capture Systems

NETL studies the costs and benefits of PSC for electricity, industry, and mobile applications. Mobile point source capture (MPSC) and storage applied to freight modes captures emissions directly from exhaust. This poster presents a framework for conducting LCA of PSC systems applied to heavy-duty trucks, freight trains, and marine vessels. The framework defines a wheels-to-storage (gate-to-grave) boundary, including energy demands (electricity, heat, and cooling requirements), solvent use and cycling, onboard system components, carbon storage in a saline aquifer, and upstream manufacturing impacts for equipment, with a suggested functional unit of 1 tonne-km. Potential data sources for analysis include material, energy, and operational data from Oak Ridge National Laboratory, GREET (Greenhouse gases, Regulated Emissions, and Energy use in Technologies) model, and scientific literature. The suggested analytical approach includes comparison to publicly available business-as-usual systems without capture across all modes of transportation, sensitivity to composition of the capture solvent, and sensitivity to capture rate variation, all of which would support a wholistic PSC business case analysis. For future consideration, analysis can be augmented with consideration of different sources of electricity (e.g., nuclear), fuel substitution, deploying supportive infrastructure such as pipeline offloading points, and downstream applications like enhanced oil recovery (EOR).

life cycle analysis (LCA)↗

Time‐Dependent Cation Selectivity of Titanium Carbide MXene in Aqueous Solution

Abstract Electrochemical ion separation is a promising technology to recover valuable ionic species from water. Pseudocapacitive materials, especially 2D materials, are up‐and‐coming electrodes for electrochemical ion separation. For implementation, it is essential to understand the interplay of the intrinsic preference of a specific ion (by charge/size), kinetic ion preference (by mobility), and crystal structure changes. Ti 3 C 2 T z MXene is chosen here to investigate its selective behavior toward alkali and alkaline earth cations. Utilizing an online inductively coupled plasma system, it is found that Ti 3 C 2 T z shows a time‐dependent selectivity feature. In the early stage of charging (up to about 50 min), K + is preferred, while ultimately Ca 2+ and Mg 2+ uptake dominate; this unique phenomenon is related to dehydration energy barriers and the ion exchange effect between divalent and monovalent cations. Given the wide variety of MXenes, this work opens the door to a new avenue where selective ion‐separation with MXene can be further engineered and optimized.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Perception Testing in Fog for Autonomous Flight

As the path towards Urban Air Mobility (UAM) continues to take shape, there are outstanding technical challenges to achieving safe and effective air transportation operations under this new paradigm. To inform and guide technology development for UAM, NASA is investigating the current state-of-the-art in key technology areas including traffic management, detect-and-avoid, and autonomy. In support of this effort, a new perception testbed was developed at NASA Ames Research Center to collect data from an array of sensing systems representative of those that could be found on a future UAM vehicle. This testbed, featuring a Light-Detection-and-Ranging (LIDAR) instrument, a long-wave infrared sensor, and a visible spectrum camera was deployed for a multiday test campaign in the Fog Chamber at Sandia National Laboratories (SNL), in Albuquerque, New Mexico. During the test campaign, fog conditions were created for tests with targets including a human, a resolution chart, and a small unmanned aerial vehicle (sUAV). Here, this paper describes in detail, the developed perception testbed, the experimental setup in the fog chamber, the resulting data, and presents an initial result from analysis of the data with the evaluation of methods to increase contrast through filtering techniques.

aeronautics↗

NASA Tech Briefs, Februrary 2013

Topics covered include: Measurements of Ultra-Stable Oscillator (USO) Allan Deviations in Space; Gaseous Nitrogen Orifice Mass Flow Calculator; Validation of Proposed Metrics for Two-Body Abrasion Scratch Test Analysis Standards; Rover Low Gain Antenna Qualification for Deep Space Thermal Environments; Automated, Ultra-Sterile Solid Sample Handling and Analysis on a Chip; Measuring and Estimating Normalized Contrast in Infrared Flash Thermography; Spectrally and Radiometrically Stable, Wideband, Onboard Calibration Source; High-Reliability Waveguide Vacuum/Pressure Window; Methods of Fabricating Scintillators With Radioisotopes for Beta Battery Applications; Magnetic Shield for Adiabatic Demagnetization Refrigerators (ADR); CMOS-Compatible SOI MESFETS for Radiation-Hardened DC-to-DC Converters; Silicon Heat Pipe Array; Adaptive Phase Delay Generator; High-Temperature, Lightweight, Self-Healing Ceramic Composites for Aircraft Engine Applications; Treatment to Control Adhesion of Silicone-Based Elastomers; High-Temperature Adhesives for Thermally Stable Aero-Assist Technologies; Rockballer Sample Acquisition Tool; Rock Gripper for Sampling, Mobility, Anchoring, and Manipulation; Advanced Magnetic Materials Methods and Numerical Models for Fluidization in Microgravity and Hypogravity; Data Transfer for Multiple Sensor Networks Over a Broad Temperature Range; Using Combustion Synthesis to Reinforce Berms and Other Regolith Structures; Visible-Infrared Hyperspectral Image Projector; Three-Axis Attitude Estimation With a High-Bandwidth Angular Rate Sensor Change_Detection.m; AGATE: Adversarial Game Analysis for Tactical Evaluation; Ionospheric Simulation System for Satellite Observations and Global Assimilative; Modeling Experiments (ISOGAME); An Extensible, User- Modifiable Framework for Planning Activities; Mission Operations Center (MOC) - Precipitation Processing System (PPS) Interface Software System (MPISS); Automated 3D Damaged Cavity Model Builder for Lower Surface Acreage Tile on Orbiter; Mixed Linear/Square-Root Encoded Single-Slope Ramp Provides Low-Noise ADC with High Linearity for Focal Plane Arrays; RUSHMAPS: Real-Time Uploadable Spherical Harmonic Moment Analysis for Particle Spectrometers; Powered Descent Guidance with General Thrust-Pointing Constraints; X-Ray Detection and Processing Models for Spacecraft Navigation and Timing; and Extreme Ionizing-Radiation-Resistant Bacterium

Source record↗

Urban Air Mobility System Testbed Using CAVE Virtual Reality Environment

Urban Air Mobility (UAM) refers to a system of air passenger and small cargo transportation within an urban area. The UAM framework also includes other urban Unmanned Aerial Systems (UAS) services that will be supported by a mix of onboard, ground, piloted, and autonomous operations. Over the past few years UAM research has gained wide interest from companies and federal agencies as an on-demand innovative transportation option that can help reduce traffic congestion and pollution as well as increase mobility in metropolitan areas. The concepts of UAM/UAS operation in the National Airspace System (NAS) remains an active area of research to ensure safe and efficient operations. With new developments in smart vehicle design and infrastructure for air traffic management, there is a need for methods to integrate and test various components of the UAM framework. In this work, we report on the development of a virtual reality (VR) testbed using the Cave Automatic Virtual Environment (CAVE) technology for human-automation teaming and airspace operation research of UAM. Using a four-wall projection system with motion capture, the CAVE provides an immersive virtual environment with real-time full body tracking capability. We created a virtual environment consisting of San Francisco city and a vertical take-off-and-landing passenger aircraft that can fly between a downtown location and the San Francisco International Airport. The aircraft can be operated autonomously or manually by a single pilot who maneuvers the aircraft using a flight control joystick. The interior of the aircraft includes a virtual cockpit display with vehicle heading, location, and speed information. The system can record simulation events and flight data for post-processing. The system parameters are customizable for different flight scenarios; hence, the CAVE VR testbed provides a flexible method for development and evaluation of UAM framework.

Marayong, Panadda↗

KNaCK-SLAM: Kinematic Navigation and Cartography Knapsack Velocity-aided LiDAR Inertial Simultaneous Localization and Mapping (SLAM)

As manned missions return to the Moon and continue on to Mars in the near future, surface navigation and mapping in extremely low solar illumination and unstructured environments without navigation aids like Global Navigation Satellite Systems (GNSS) becomes more important than even. This work explores the use of LiDAR-based Simultaneous Localization and Mapping (SLAM) to solve those problems. A LiDAR-based SLAM system be deployed as a self-contained instrument independent of external sensor inputs, and can operate in unlit environments where Vision-based SLAM system are inoperable. Furthermore, the advent of chip-scale frequency modulated continuous wave (FMCW) LiDAR technology provides Doppler-velocity information for each sensed point in the scene, which can be used to further constrain localization error in the SLAM front-end. Here we discuss the development of SLAM algorithm that makes use of the unique velocity and range sensing capabilities of FMCW-LiDAR based sensors for rover and kinematic (i.e. person-mounted) mobile navigation and terrain mapping applications for surface exploration and scientific investigations.

Kyle Miller↗

Advanced EMU Portable Life Support System (PLSS) and Shuttle/ISS EMU Schematics, A Comparison

In order to be able to adapt to differing vehicle interfaces such as suitport and airlock, adjust to varying vehicle pressure schedules, tolerate lower quality working fluids, and adapt to differing suit architectures as dictated by a range of mission architectures, the next generation space suit requires more adaptability and robustness over that of the current Shuttle/ISS Extra-vehicular Mobility Unit (EMU). While some features have been added to facilitate interfaces to differing vehicle and suit architectures, the key performance gains have been made via incorporation of new technologies such as the variable pressure regulators, Rapid Cycle Amine swing-bed, and Suit Water Membrane Evaporator. This paper performs a comparison between the Shuttle/ISS EMU PLSS schematic and the Advanced EMU PLSS schematic complete with a discussion for each difference.

Campbell, Colin↗

Advanced EMU Portable Life Support System (PLSS) and Shuttle/ISS EMU Schematics, a Comparison

In order to be able to adapt to differing vehicle interfaces such as suitport and airlock, adjust to varying vehicle pressure schedules, tolerate lower quality working fluids, and adapt to differing suit architectures as dictated by a range of mission architectures, the next generation space suit requires more adaptability and robustness over that of the current Shuttle/ISS Extra-vehicular Mobility Unit (EMU). While some features have been added to facilitate interfaces to differing vehicle and suit architectures, the key performance gains have been made via incorporation of new technologies such as the variable pressure regulators, Rapid Cycle Amine swing-bed, and Suit Water Membrane Evaporator. This paper performs a comparison between the Shuttle/ISS EMU PLSS schematic and the Advanced EMU PLSS schematic complete with a discussion for each difference.

Campbell, Colin↗

Nuclear Safety [Vol. 32, No. 4, October-December 1991]

Nuclear Safety is a review journal that covers significant developments in the field of nuclear safety. Its scope includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated. Table of Contents for this issue follows. GENERAL SAFETY CONSIDERATIONS: 477 Report on the International Symposium on the Use of Probabilistic Safety Assessment for Operational Safety—PSA '91, S. Chakraborty and M. Khatib-Rahbar; 488 Good Relationships Are Pivotal in Nuclear Data Bases, A. S. Heger and B. V. Koen; 494 Technical Note: The Interagency Nuclear Safety Review Panel's Evaluation of the Ulysses Space Mission, J. A. Sholtis, Jr., D. A. Huff, L. B. Gray, N. P. Klug, and R. O. Winchester; ACCIDENT ANALYSIS: 502 The Severe Accident Analysis Program for the Savannah River Nuclear Production Reactors, M. L. Hyder; CONTROL AND INSTRUMENTATION: 511 A Framework for Selecting Suitable Control Technologies for Nuclear Power Plant Systems, R. A. Kisner; DESIGN FEATURES: 521 Containments for Gas-Cooled Power Reactors History and Status, P.W. Williams; ENVIRONMENTAL EFFECTS: 537 Indoor Radon: A Natural Risk, N. H. Harley and J.H. Harley; On the Importance of the Atmospheric Parameters in the Fission Products Distribution of a Severe Reactor Accident, M. C. Barla and A. R. Bayulken; Book Review: Health Effects of Exposure to Low Levels of Ionizing Radiation BEIR V, C. R. Richmond; WASTE AND SPENT FUEL MANAGEMENT: 555 Activities Related to Waste and Spent Fuel Management, M. D. Muhlheim and E. G. Silver OPERATING EXPERIENCES: 567 Effects of Component Aging on the Westhinghouse Control Rod Drive System, K. Sullivan and W. Gunther; 577 Reactor Shutdown Experience, Compiled by J. W. Cletcher, 580 Selected Safety-Related Events, Compiled by G. A. Murphy; 582 Operating U 8 Power Reactors, Compiled by M. D. Muhlheim and E. G. Silver, RECENT DEVELOPMENTS: 596 General Administrative Activities, Compiled by M. D. Muhlheim and E. G. Silver; 610 Reports, Standards, and Safety Guides, D. S. Queener; 614 Proposed Rule Changes as of June 30, 1991; ANNOUNCEMENTS: 520 Workshop on PC PRAISE: A Probabilistic Fracture Mechanics Personal Computer Code for Nuclear Power Plant Piping Reliability Assessment; 536 Fifth Workshop on Nuclear Power Plant Containment Integrity; 624 New OECD "International Information System on Occupational Exposure (ISOE)"; 625 Harvard School of Public Health Announces Short Courses; 625 Eighth Power Plant Dynamics, Control and Testing Symposium; 626 Second Training Course on Off-Site Emergency Planning and Response for Nuclear Accidents; 618 The Authors; 622 Reviewers of Nuclear Safety, Vol 32.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Satellite sound broadcasting system, portable reception

Studies are underway at JPL in the emerging area of Satellite Sound Broadcast Service (SSBS) for direct reception by low cost portable, semi portable, mobile and fixed radio receivers. This paper addresses the portable reception of digital broadcasting of monophonic audio with source material band limited to 5 KHz (source audio comparable to commercial AM broadcasting). The proposed system provides transmission robustness, uniformity of performance over the coverage area and excellent frequency reuse. Propagation problems associated with indoor portable reception are considered in detail and innovative antenna concepts are suggested to mitigate these problems. It is shown that, with the marriage of proper technologies a single medium power satellite can provide substantial direct satellite audio broadcast capability to CONUS in UHF or L Bands, for high quality portable indoor reception by low cost radio receivers.

Golshan, Nasser↗

Direct broadcast satellite-radio, receiver development

The status of the ongoing Direct Broadcast Satellite-Radio (DBS-R) Receiver Development Task being performed at the Jet Propulsion Laboratory, California Institute of Technology (JPL) is reported. This work is sponsored by the Voice of America/U.S. Information Agency through an agreement with NASA. The objective of this task is to develop, build, test, and demonstrate a prototype receiver that is compatible with reception of digital audio programs broadcast via satellites. The receiver is being designed to operate under a range of reception conditions, including fixed, portable, and mobile, as well as over a sufficiently wide range of bit rates to accommodate broadcasting systems with different cost/audio quality objectives. While the requirements on the receiver are complex, the eventual goal of the design effort is to make the design compatible with low cost production as a consumer product. One solution may be a basic low cost core design suitable for a majority of reception conditions, with optional enhancements for reception in especially difficult environments. Some of the receiver design parameters were established through analysis, laboratory tests, and a prototype satellite experiment accomplished in late 1991. Many of the necessary design trades will be made during the current simulation effort, while a few of the key design options will be incorporated into the prototype for evaluation during the planned satellite field trials.

Vaisnys, A.↗

Initial Design Guidelines for Onboard Automation of Flight Path Management

Achieving the National Academy of Science’s vision of advanced aerial mobility will depend on significant developments in automation to achieve safe and efficient operations. Flight path management (FPM), a major category of automation functionality needed to achieve this vision, will provide dynamic management of an aircraft’s flight path, ensuring that it remains feasible to fly to mission completion, deconflicted from hazards, coordinated with other traffic, flexible to accommodate future disturbances, and optimized to meet business objectives. While efforts are underway to advance FPM technology for the Urban Air Mobility application, initial design guidelines are presented for FPM automation capabilities to achieve each of these objectives based on 15+ years of prior FPM automation research and development. Methods to efficiently account for uncertainty in the prediction of trajectories are described, as are additional considerations for prioritizing safety in the design of FPM automation capabilities and interactions between aircraft. Recommendations are supported by extensive experience gained via previous work with the FPM reference automation system, Autonomous Operations Planner, developed by NASA. By employing capable FPM automation supported by cooperative operational flight rules and information sharing, future aircraft operators will benefit from an increased ability to plan and execute safe and efficient flights and to achieve mission success in a dynamic airspace.

Flight Path Management, FPM, AOP, UAM, deconflicti↗

Initial Design Guidelines for Onboard Automation of Flight Path Management

Achieving the National Academy of Science’s vision of advanced aerial mobility will depend on significant developments in automation to achieve safe and efficient operations. Flight path management (FPM), a major category of automation functionality needed to achieve this vision, will provide dynamic management of an aircraft’s flight path, ensuring that it remains feasible to fly to mission completion, deconflicted from hazards, coordinated with other traffic, flexible to accommodate future disturbances, and optimized to meet business objectives. While efforts are underway to advance FPM technology for the Urban Air Mobility application, initial design guidelines are presented for FPM automation capabilities to achieve each of these objectives based on 15+ years of prior FPM automation research and development. Methods to efficiently account for uncertainty in the prediction of trajectories are described, as are additional considerations for prioritizing safety in the design of FPM automation capabilities and interactions between aircraft. Recommendations are supported by extensive experience gained via previous work with the FPM reference automation system, Autonomous Operations Planner, developed by NASA. By employing capable FPM automation supported by cooperative operational flight rules and information sharing, future aircraft operators will benefit from an increased ability to plan and execute safe and efficient flights and to achieve mission success in a dynamic airspace.

Flight Path Management↗

Pd-promoted reduction and restructuring of an In 2 O 3 -based catalyst for CO 2 hydrogenation at room temperature

An unconventional reaction mechanism in an In 2 O 3 /Pd(1 1 1) inverse model catalyst for the CO 2 hydrogenation reaction has been uncovered: In 2 O 3 is partially reduced at room temperature in a reaction atmosphere as a result of its direct contact with Pd(1 1 1), which is an efficient H 2 splitter. The reduction induces changes in surface free energy, leading to a dynamical restructuring at the In 2 O 3 /Pd(1 1 1) interface via formation of InO x and outward diffusion of Pd, as revealed by ambient pressure X-ray photoelectron spectroscopy, X-ray absorption spectroscopy and density functional theory simulations. This dynamical restructuring eventually promotes the growth of 2D InPd y O x nanodomains as the catalytically active phase and the exclusive formation of methanol upon hydrogenation of CO 2 at room temperature. A comparable high selectivity toward CH 3 OH was found in more realistic bulk catalytic systems (2 wt% Pd/In 2 O 3 catalyst and commercial CZA catalyst). Scanning tunneling microscopy under ultrahigh vacuum and ambient pressure reaction atmospheres further reveals the structural dynamics at the InO x /Pd(1 1 1) interface, where we follow in situ the evolution of the InO x particles on Pd(1 1 1) and the mobility of the InPd y O x nanodomains in a CO 2 + H 2 environment. The present findings of the formation of a mixed oxide phase in a dynamically restructuring metal/reducible-oxide interface indicate further implications for other heterogeneous catalytic systems beyond the present CO 2 hydrogenation example and highlight the importance of in situ investigations.

36 MATERIALS SCIENCE↗

Scanning Mobility Particle Sizer (SMPS) Instrument Handbook

The Model 3936 Scanning Mobility Particle Spectrometer (SMPS) measures the size distribution of aerosols ranging from 10 nm up to 1000 nm. The SMPS uses a bipolar aerosol charger to keep particles within a known charge distribution. Charged particles are classified according to their electrical mobility, using a long-column differential mobility analyzer (DMA). Particle concentration is measured with a condensation particle counter (CPC). The SMPS is well-suited for applications including: nanoparticle research, atmospheric aerosol studies, pollution studies, smog chamber evaluations, engine exhaust and combustion studies, materials synthesis, filter efficiency testing, nucleation/condensation studies, and rapidly changing aerosol systems.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Methane Integrated Monitoring and Measurement System Design

Methane (CH 4 ), an abundant greenhouse gas, is the second largest contributor to global warming after carbon dioxide (CO 2 ). In comparison to CO 2 , CH 4 has a larger warming effect over a much shorter lifetime. While technologies to radically reduce global carbon dioxide emissions are materializing, rapid reductions in methane emissions are needed to limit near-term warming. Methane is primarily emitted as a byproduct from agricultural activities and energy extraction/utilization and is currently monitored via bottom-up (i.e., activity level) or top-down (via airborne or satellite retrievals) approaches. However, significant methane leaks remain undetected, and emission rates are challenging to characterize with current monitoring frameworks. In this report, we study methane leaks from oil and gas infrastructure using a tiered monitoring approach that combines bottom-up and top-down approaches in an integrated framework. We describe the individual advantages of bottom-up and top-down sensors in both stationary and mobile settings before characterizing how a fully integrated framework can improve predictions and uncertainties of potential leak locations and their emission rates. Further, we study the impact of different atmospheric (wind) conditions on integrated methane monitoring and develop a probabilistic approach to optimal sensor placement, thereby shortening detection times and improving monitoring capabilities. Last, we discuss how biogenic flux modeling can be used to improve assessment of background methane concentrations needed to fully assess the sensitivity of a tiered monitoring system.

54 ENVIRONMENTAL SCIENCES↗